Cartridges of the type to which my invention relates have been known and used for many years in various industries. In the construction industry, for example, it is well known to market caulking compounds and similar putty-like or semi-solid materials in cylindrical cartridges that have protruding nozzles at one end, through which the contents may be extruded in continuous lengths. The material so extruded has a cross-sectional form and dimension corresponding to the orifice through which it is extruded. Such cartridges are adapted to be placed in a holder with a propellable-repellable plunger at one end, the plunger being operable to exert pressure on a bottom member or plug of the cartridge. The bottom plug is axially retractable within the cylindrical body of the cartridge and is adapted to be pushed by the plunger toward the nozzle end of the cartridge. Such plungers are usually operable by a trigger and ratchet mechanism which enables the user, by squeezing the trigger, to move the bottom plug of the cartridge any selected distance toward the other end thereof and thus to cause a pre-determined quantity of the cartridge contents to be extruded through the nozzle. In other similar cartridge holders, the plunger is connected to a screw mechanism which may be operated by a rotatable handle or crank to exert pressure on the movable bottom plug of the cartridge. Typically, the ratchet mechanism can exert pressure up to 400 lbs/in.sup.2.
In the kitchens of fast food restaurants, there is a need for utensils and dispensers which provide maximum speed, convenience and quantity control. Such utensils and dispensers must, of course, meet the highest sanitary standards. Also, it is essential that maximum uniformity be maintained in sauces served by restaurants of the same franchisor, whereever they are located. Cartridge dispensers have been found to fulfill these needs and they are being used increasingly by franchisors to make the operations at their stores and restaurants more efficient and economical.
U.S. Pat. No. 3,884,396 discloses a disposable cartridge structure comprising a cylindrical container body made of a foil-laminated, food-grade paperboard material, a separate dispensing head of molded plastic, and a separate plug of molded plastic. The head and plug are secured to the body by means of strips of shrinkable plastic heat-sealing tape. While the foregoing cartridge structure has been received with favor, it has several drawbacks which have somewhat limited its utilization. In this regard, the cartridge arrangement shown in U.S. Pat. No. 3,884,396 requires complex and expensive equipment for use in connection with the assembly and filling operations. Further, due to the multitude of parts, operational difficulties are relatively common during such operations with the result that the speed of filling and assembly cannot be maintained at the desired levels.
Difficulties have also been experienced in the shipping of the load cartridges of the type shown in the foregoing patent. Typically, the cartridges after being filled with sauce are are arranged in boxes and the boxes stacked one upon the other. Such stacking can produce up to several hundred pounds of force on some of the cartridges. The load forces create stress points at the sharply angled regions of the dispensing head sufficient to cause fracture and leakage of the contents of the cartridges.